General ACCAACCA PER

Hi, I have a query regarding ACCA PER time verification for a previous role. I worked in a finance-related role at a large approved employer for approximately 12 months. All of my performance objectives have already been signed off from other roles, so I only need to get this period of time verified. However, my previous line manager is unwilling to complete the ACCA online verification due to not wanting to register their details. I contacted the employer’s HR/references team, and they are able to provide a formal written confirmation of my employment (including dates, role, and duties), but they cannot complete the ACCA online supervisor sign-off due to company policy. Would ACCA accept a formal HR letter as alternative evidence for time-only PER in this situation? Has anyone come across similar cases, and what was the outcome? Thanks in advance.